Re: pfTexGen problems

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Rémi Arnaud (remi++at++remi.engr.sgi.com)
Fri, 26 Sep 1997 11:26:07 -0700 (PDT)

Steve Baker wrote:
>
>
> Hi.
>
> I'm using pfTexGen with SPHEREMAP mode to generate cute shiney reflections.
>
> As a test, I modelled a white sphere, and picked a suitably distorted
> environment map with sky in the top half of the circle and ground in the
> bottom half.
>
> I model the sphere under a pfDCS node - and everything looks great - I
> spin the DCS and the ground stays reflected in the bottom half of the
> sphere and the sky in the top half.
>
> However, if I roll the eyepoint inverted (using pfChanView for example)
> the reflection rolls with me. So, the sky is now reflected in the wrong part
> of the sphere. The pfESky shows blue on the bottom half of the screen - but
> that bottom half of the sphere is still green.
>
> Is this an inherent problem with pfTexGen or am I doing something wrong ?
>
> Could it be something to do with when the pfTexGen is pfApply'ed ? Right
> now, I attach the pfTexGen to the pfGeoState - so I don't have control of
> when this happens.
>

 SPHEREMAP works in eye space. It consider the eye space the coordinate
 system that defines the up/down/left/right directions.
 I guess that you will have to 'undo' the eye rotations using the texture matrix.

 [pfApplyTMat in 2.2]
 [mmode(MTEXTURE); loadmatrix(m); mmode(MVIEWING); before 2.2]

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